Variable valve apparatus and muffler provided with the same

ABSTRACT

A variable valve apparatus includes: a housing having a pair of shaft holes and a gate hole formed in the housing; a gate provided to selectively open the gate hole; a shaft provided in the shaft holes and connected to the gate; and a spring provided on the shaft so as to elastically support the gate, in which a gap is formed between the gate and the housing. The variable valve apparatus may be provided as part of a muffler installed in a vehicle.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims under 35 U.S.C. §119(a) priority to and thebenefit of Korean Patent Application No. 10-2012-0145735 filed in theKorean Intellectual Property Office on Dec. 13, 2012, the entirecontents of which are incorporated herein by reference.

BACKGROUND

(a) Field of the Invention

The present invention relates to a variable valve apparatus and amuffler provided with the same, and more particularly, to a variablevalve apparatus capable of reducing touching noise and booming noise,and a muffler provided with the variable valve apparatus, where themuffler can be installed in a vehicle.

(b) Description of the Related Art

Generally, in a gasoline engine used in a vehicle or the like(hereinafter, referred to as an engine), silence without noise isrequired in an idle rotation region of 750 RPM and a common-use regionof 2500 to 3000 RPM, and high power is required in a fast rotationregion of 3000 RPM or more, rather than silence.

Most engine noise comes from exhaust sound discharged from the engine,and a variety of research has been conducted on a muffler in order tohave the muffler not only suppress the exhaust noise but also exhibithigh power.

It is known to provide a muffler in which a variable valve is mounted soas to be opened/closed according to exhaust gas pressure. In aconventional variable valve, however, noise may be caused by frequentcontacts between a gate and a housing due to change in the exhaust gaspressure.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention andtherefore it may contain information that does not form the prior artthat is already known in this country to a person of ordinary skill inthe art.

SUMMARY

The present invention provides a variable valve apparatus capable ofreducing touching noise and booming noise, and a muffler provided withthe variable valve apparatus, where the muffler can be installed in avehicle.

An exemplary embodiment of the present invention provides a variablevalve apparatus including: a housing having a pair of shaft holes and agate hole formed therein; a gate provided to selectively open the gatehole; a shaft provided in the shaft holes and connected to the gate; anda spring provided on the shaft so as to elastically support the gate, inwhich a gap having a predetermined size may be formed between the gateand the housing.

A metal mesh for supporting the gate may be provided in the housing at aposition adjacent to the shaft.

A guide space may be formed between the housing and the gate so as toguide exhaust gas to flow into the gap.

The housing may have an inclined portion formed to be inclined outward,the gate may have a protruding portion protruding to be inclined to aninside of the housing, and the guide space may be defined as a spacebetween the inclined portion and the protruding portion.

The gate may be completely inserted into the housing withoutinterference.

One end of the gate and one end of the housing, which form the gap, maybe positioned on the same plane.

The shaft holes may be provided with a bushing to support the shaft.

The predetermined size may range from about 0.5 mm to 2.0 mm.

Another exemplary embodiment of the present invention provides a mufflerhaving a variable valve apparatus, including: a plurality of chambersformed by partitioning an inside of a housing using partition walls; aninlet pipe for introducing exhaust gas into the housing; a dischargepipe for discharging exhaust gas introduced to the chambers to theoutside; an inner pipe directly connecting the chambers inside thehousing; and a variable valve apparatus formed in the downstream side ofthe inner pipe and automatically controlling an opening/closing amountaccording to exhaust gas pressure, in which the variable valve apparatusincludes: the housing having a pair of shaft holes and a gate holeformed therein; a gate provided to selectively open the gate hole; ashaft provided in the shaft holes and connected to the gate; and aspring provided on the shaft so as to elastically support the gate, anda gap having a predetermined size may be formed between the gate and thehousing.

A metal mesh for supporting the gate may be provided in the housing at aposition adjacent to the shaft.

A guide space may be formed between the housing and the gate so as toguide exhaust gas to flow into the gap.

The housing may have an inclined portion formed to be inclined outward,the gate may have a protruding portion protruding to be inclined to theinside of the housing, and the guide space may be defined as a spacebetween the inclined portion and the protruding portion.

The gate may be completely inserted into the housing withoutinterference.

One end of the gate and one end of the housing, which form the gap, maybe positioned on the same plane.

The shaft holes may be provided with a bushing to support the shaft.

The predetermined size may range from about 0.5 mm to 2.0 mm.

According to the exemplary embodiments of the present invention, thevariable valve apparatus and the muffler provided with the same mayreduce touching noise and booming noise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a variable muffler according to anexemplary embodiment of the present invention.

FIG. 2 is a perspective view of the variable muffler according to theexemplary embodiment of the present invention.

FIG. 3 is a cross-sectional view of the variable valve according to theexemplary embodiment of the present invention.

FIG. 4 is an exploded parts view of the variable valve according to theexemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, only certain exemplaryembodiments of the present invention have been shown and described,simply by way of illustration. As those skilled in the art wouldrealize, the described embodiments may be modified in various differentways, all without departing from the spirit or scope of the presentinvention. Throughout the specification, like reference numeralsrepresent the same constituent elements. In the drawings, the thicknessof layers, films, panels, regions, etc., are exaggerated for clarity.When an element such as layer, film, region, or plate is referred to asbeing “on” another element, it may include not only a case in which anelement is directly on another element but also a case in which anotherelement is interposed therebetween. In contrast, when an element isreferred to as being “directly on” another element, there are nointervening elements present.

It is understood that the term “vehicle” or “vehicular” or other similarterm as used herein is inclusive of motor vehicles in general such aspassenger automobiles including sports utility vehicles (SUV), buses,trucks, various commercial vehicles, watercraft including a variety ofboats and ships, aircraft, and the like, and includes hybrid vehicles,electric vehicles, plug-in hybrid electric vehicles, hydrogen-poweredvehicles and other alternative fuel vehicles (e.g. fuels derived fromresources other than petroleum). As referred to herein, a hybrid vehicleis a vehicle that has two or more sources of power, for example bothgasoline-powered and electric-powered vehicles.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

An exemplary embodiment of the present invention will hereinafter bedescribed in detail with reference to the accompanying drawings. FIG. 1is a top plan view of a variable muffler according to an exemplaryembodiment of the present invention, and FIG. 2 is a perspective view ofthe variable muffler according to the exemplary embodiment of thepresent invention.

Referring to FIGS. 1 and 2, the variable muffler according to theexemplary embodiment of the present invention includes a housing 100, aninlet pipe 110, an outlet pipe 120, and an inner pipe 130 providedinside the housing 100. The inside of the housing 100 is partitionedinto a plurality of chambers 101, 102, and 103 by partition walls 140formed of a perforated plate.

The inlet pipe 110 has one end exposed to the outside of the housing 100and the other end formed to introduce exhaust gas into the housing 100.Further, the inlet pipe 110 is laid in such a manner that one endthereof is inserted into the housing 100, in order to discharge exhaustgas introduced to the housing to the rear side of the housing 100.

The partition walls 140 include first and second partition walls 141 and142 provided inside the housing, and the first and second partitionwalls 141 and 142 and the housing 100 form the first, second, and thirdchambers 101, 102, and 103.

The inlet pipe 110 communicates with the third chamber 103 through thefirst chamber 101, the first partition wall 141, and the secondpartition wall 142.

The outlet pipe 120 has a plurality of penetration holes 123 formed tocommunicate with the second chamber 102. The plurality of penetrationholes 123 may be formed through the outer circumferential surface of theoutlet pipe 120, thereby obtaining a noise reduction effect. The secondchamber 102 may be filled with a noise absorbing material 300, and thenoise absorbing material 300 may be formed of glass wool and serve toreduce flow-induced noise occurring while exhaust gas passes through thesecond chamber 102.

The inner pipe 130 is provided to communicate with the first and thirdchambers 101 and 103. The first partition wall 141 has a plurality offirst partition wall penetration holes 143 formed to connect the firstand second chambers 101 and 102.

The outlet pipe 120 may be formed in a U-shape. The outlet pipe 120 maybe provided to pass through the first to third chambers 101 to 103 oneor more times. The outlet pipe 120 may be provided to sequentially passthrough the first chamber 101, the second chamber 102, the third chamber103, the second chamber 102, the first chamber 101, the second chamber102, and the third chamber 103.

A variable valve 200 for controlling the amount of exhaust gas isinstalled in the downstream side of the inner pipe 130, that is, at aninner pipe exit 132.

FIG. 3 is a cross-sectional view of the variable valve according to theexemplary embodiment of the present invention, and FIG. 4 is an explodedparts view of the variable valve according to the exemplary embodimentof the present invention.

Referring to FIGS. 3 and 4, the variable valve apparatus 200 includes apair of shaft holes 212, a housing 210 having a gate hole 214 formedtherein, a gate 220 provided to selectively open the gate hole 214, ashaft 230 provided in the shaft holes 212 and connected to the gate 220,and a spring 240 provided on the shaft 230 so as to elastically supportthe gate 220. Further, as illustrated in FIG. 3, a gap G having apredetermined size is formed between the gate 220 and the housing 210,and the predetermined size may range from about 0.5 mm to 2.0 mm. Thegate 220 has connection holes 226 formed therein, and the shaft 230 isinserted into the connection holes 226 so as to rotatably connect thegate 220 and the housing 210.

A metal mesh 250 for supporting the gate 220 may be provided in thehousing 210 at a position adjacent to the shaft 230. The metal mesh 250may be provided between the housing 210 and the gate 220, and may reducenoise caused by contact between the housing 210 and the gate 220.Between the housing 210 and the gate 220, a guide space 260 may beformed to guide exhaust gas to flow into the gap G.

The housing 210 may have an inclined portion 216 formed to be inclinedoutward, the gate 220 may have a protruding portion 222 protruding to beinclined toward the inside of the housing 210, and the guide space 260may be defined as a space between the inclined portion 216 and theprotruding portion 222.

When an engine RPM increases, the pressure of exhaust gas introduced tothe variable valve apparatus 200 opens the gate 220. The gate 220 isslowly opened during a low-speed period. However, when excessivepressure fluctuation occurs during a medium and low-speed period, thegate 220 may come in contact with the housing 210 while the gate 220 isvibrated. However, the guide space 260 serves as a kind of diffuser, andthe pressure in the guide space 260 may be reduced. Accordingly,pressure fluctuation may be reduced to prevent the vibration of thevalve. Therefore, it is possible to suppress noise from being caused bycontact between the gate 220 and the housing 210.

The gate 220 may be completely inserted into the housing 210 withoutinterference. Such a structure may suppress noise from being caused bycontact between the gate 220 and the housing 210. Further, one end 221of the gate and one end 211 of the housing, which form the gap G, may bepositioned on the same plane. The gate 220 may include the protrudingportion 222 formed to protrude to the inside of the housing 210 and arecess portion 224 formed inside the protruding portion 222 so as toprotrude to the outside of the housing 210. The shaft holes 212 areprovided with a bushing 270 to support the shaft 230.

The recess portion 224 of the variable valve apparatus 200 according tothe exemplary embodiment of the present invention may receive thepressure of exhaust gas transferred to the variable valve apparatus 200such that the gate 220 is rotated about the shaft 230. The gate 220 maybe opened by the shape of the recess portion 224, even though low-speedexhaust gas is transferred to the gate 220.

The gap G between the gate 220 and the housing 210 may block noisecaused by contact between the gate 220 and the housing 210, and themetal mesh 250 may be mounted between the gate 220 and the housing 210so as to block contact noise between the gate 220 and the housing 210.

The size of the gap G, that is, the predetermined size may range fromabout 0.5 mm to 2.0 mm, and may prevent contact between the gate 220 andthe housing 210 by manufacturing tolerance or vibration. When a gaplarger than the gap G is formed, booming noise may occur. Therefore, thesize of the gap G is limited in the range of about 0.5 mm to 2.0 mm.

The guide space 260 between the housing 210 and the gate 220 guidesexhaust gas to flow into the gap G. When the gate 220 is to come incontact with the housing 210 by vibration or the like, the guide space260 serves as a kind of cushion, thereby preventing contact or reducingimpact and noise, even though the gate 220 comes in contact with thehousing 210.

As illustrated in FIG. 4, a stepped portion 216 may be formed in aportion of the housing 210, which is not adjacent to the shaft 230, inorder to form the guide space 260. The guide space 260 may be formed bythe shape of the stepped portion 216. As described above, the guidespace 260 guides exhaust gas, and serves as a kind of cushion by thepressure of exhaust gas between the gate 220 and the housing 210.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is:
 1. A variable valve apparatus comprising: a housinghaving a pair of shaft holes and a gate hole formed therein; a gateprovided to selectively open the gate hole; a shaft provided in theshaft holes and connected to the gate; and a spring provided on theshaft so as to elastically support the gate, wherein a gap having apredetermined size is formed between the gate and the housing.
 2. Thevariable valve apparatus of claim 1, wherein: a metal mesh forsupporting the gate is provided in the housing at a position adjacent tothe shaft.
 3. The variable valve apparatus of claim 1, wherein: a guidespace is formed between the housing and the gate so as to guide exhaustgas to flow into the gap.
 4. The variable valve apparatus of claim 3,wherein: the housing has an inclined portion formed to be inclinedoutward, the gate has a protruding portion protruding to be inclined toan inside of the housing, and the guide space is defined as a spacebetween the inclined portion and the protruding portion.
 5. The variablevalve apparatus of claim 4, wherein: the gate is completely insertedinto the housing without interference.
 6. The variable valve apparatusof claim 3, wherein: one end of the gate and one end of the housing,which form the gap, are positioned on the same plane.
 7. The variablevalve apparatus of claim 1, wherein: the shaft holes are provided with abushing to support the shaft.
 8. The variable valve apparatus of claim1, wherein: the predetermined size ranges from about 0.5 mm to 2.0 mm.9. A muffler having a variable valve apparatus, comprising: a pluralityof chambers formed by partitioning an inside of a housing usingpartition walls; an inlet pipe for introducing exhaust gas into thehousing; a discharge pipe for discharging exhaust gas introduced intothe chambers to the outside; an inner pipe directly connecting thechambers inside the housing; and a variable valve apparatus formed in adownstream side of the inner pipe and automatically controlling anopening/closing amount according to exhaust gas pressure, wherein thevariable valve apparatus comprises: the housing having a pair of shaftholes and a gate hole formed therein; a gate provided to selectivelyopen the gate hole; a shaft provided in the shaft holes and connected tothe gate; and a spring provided on the shaft so as to elasticallysupport the gate, and a gap having a predetermined size is formedbetween the gate and the housing.
 10. The muffler of claim 9, wherein: ametal mesh for supporting the gate is provided in the housing at aposition adjacent to the shaft.
 11. The muffler of claim 9, wherein: aguide space is formed between the housing and the gate so as to guidethe exhaust gas to flow into the gap.
 12. The muffler of claim 11,wherein: the housing has an inclined portion formed to be inclinedoutward, the gate has a protruding portion protruding to be inclined tothe inside of the housing, and the guide space is defined as a spacebetween the inclined portion and the protruding portion.
 13. The mufflerof claim 12, wherein: the gate is completely inserted into the housingwithout interference.
 14. The muffler of claim 11, wherein: one end ofthe gate and one end of the housing, which form the gap, are positionedon the same plane.
 15. The muffler of claim 9, wherein: the shaft holesare provided with a bushing to support the shaft.
 16. The muffler ofclaim 9, wherein: the predetermined size ranges from about 0.5 mm to 2.0mm.